Electrolytic cell



C. P. -IUWNSENDl ELECTROLYTIC CELL. APPLICATION FILED IuLv 24. Isn,

Patented June 10, 1919.

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fll'fonncgs ETD ST Esn i CLINTON PAUL TOWNSEND, OF vWASHINGII'ON, DISTRICT OF COLUMBIA, ASSIC'N'OR TO HOOKER ELECTROCI-IEMICAL NEW YORK.

COMPANY, 0F NEW YORK, N. Y., A CORPORATIONy OF ELEoTRoLY'rIc CELL.

Specication of Letters Patent. Pateted June 10, 1919.

Application led uly 24, 1917.' Serial No. 182,504.

TowNsEND, a citizen of the United States,-

residing at Washington, in the District of `Golumbia,;have invented certain new and useful Improvements in Electrolytic Cells, 'I

of which the following is a specificati-on.

This invention relates to electrolytic cells for producing chlorin or other gaseous products, a primary object of the invention being toprovide in conjunction with electrolytic cells producing chlorin or other gases, means for avoiding the diluting effect upon such gases of atmospheric air entering the cell through fissures or leaks in the cell structure, or with the iniowing electrolyte, or otherwise. The invention comprises also the method whereby this result is attained'.

The invention 'willbe described as applied point to maintain in chlorin-producing cells to a cell of the diaphragm type producing chlorin and caustic soda by the electrolytic decomposition of brine, but as will hereinafter appear the invention is not restricted to cells of this articular type,

It is desirab e from an operating standa gas-pressure which does not exceed atmos-` pheric pressure, andwhich is preferably slightly below atmospheric, since under these conditions no escape of chlorin can occur into the atmosphere through such minute fissures as are liable to exist in the structure,

for example in the cell-body or cover, around the anode leads, etc. This is usually accomplished by withdrawing the chlorin e under slight suction produced by a fan or equivalent means, and presents the disadvantage (for certain purposes for which a highly concentrated gas is desired) that the chlorin is diluted to whatever extent airy may enter the cell from without.

The purpose of this invention is to see cure the operating advantagedue to maintaining atmospheric or lower .pressures within the cell while at the same time removing a substantial proportion of the evolved chlorin or other gas, or even substantially all thereof, under a pressure which may slightly or considerably exceed that of the atmosphere. vThis is accomplished in a representative embodiment of the invention by providing a plurality of gas outlets from the anode compartment slight, but should be suiiicient to cause a definite flow of the gas into the gas distributing or collecting system. Or if desired, the positive pressure may attain con siderable magnitudes, as explained below.

The accompanying drawing, in which the figure is a transverse vertical section of an electrolytic cell-of the vertical-diaphragm type, illustrates one mode of carrying the invention 'intofefect In said drawing, 1 represents the concrete base of the cell, and 2 one of the end walls thereof, the cellbody being of elongated U-form with vertical end-mcmbers. 3, 3 represents side plates which may be o-f Portland cement or cement mixtures, or of any appropriate insulating or insulated material, these side plates extending between the upper portions of the end-members 2. 4 is the cell cover. The sides of the cell are closed by sheet-metal flanged cathode compartments 5, provided with the usualsoutlets for caustic solution and hydrogen, and which may be secured in place in any desired way, for example by means of wedges or cams 6 passing through slots in the horizontal anglebars 7, and engaging the Hanges 8 of the cathode compartments. 9 represents the perforated steel'plate cathodes and 10 the diaphragme, usually of asbestos paper. 11 are the graphite anodes and 12 the anode leads, also of graphite, the latter illustrated as projecting upwardly through the ycellcover 4. 13 indicates the anode electrolyte (anolyte) consisting. in this case of a strong sodium chlorid solution. Any appropriate means may be used' for maintaining and a suction fan indicated 'at 15 to maintain a very slight sub-atmospheric pressure within the cell.

As a typical means for withdrawing chlorin gas under positive pressure even while maintaining a sub-atmospheric pressure within the gas-space of the cell, I have illustrated longitudinal collectingchannels 16 formed within or extending along the lower edges of the side plates 3, and communicating with gas conduits 17 extending upwardly through these side plates. These conduits (or the gas system connected therewith) are provided with appropriate pressure controlling devices, typied by the cocks 18. Inasmuch as the lower edges ot' the collecting: channels 16 are below the normal liquid level in the anode compartment (indicated at 19) it will be obvious that the chlorin may be drawn from the conduits 17 under any pressure up to that represented by the hydrostatic head of liquid above the depending walls ot' these channels. As stated above, a very small positive pressure will suice to secure the desired advantage of freedom Jfrom dilution by infiltration of atmospheric air; but it will be understood that the gas may if desired be collected under verv considerable pressures by corresl'iondingly increasing the hydrostatic head of liquid in the anode compartment.

The term positive pressure is used herein to include any degree of pressure which will suiiice under operating conditions to prevent dilution of chlorin by the infil evolved gas before it reaches said gas-space.

2. In combination with an electrolytic celll for producting chlorin, means for maintaining atmospheric or lower pressures within the gas-space of the cell, and means disposed below the surface of the electrolyte for collecting the evolved clilorin before it reaches said gas-space. l

3. In the electrolytic production of chlorin, the step which consists in simultaneously withdrawing the evolved chlorin at a plurality of points and at diering pressures.

4:. In the electrolytic production of chlorin, the steps which consist in withdrawing a portion at least of the evolvedgas u nder positive pressure, while maintaining within the gas-space of the cell a pressure not exceeding atmospheric. l

5. In the electrolytic production of chlorin, the steps which consist in withdrawing a portion at least of the evolved chlorin under positive pressure while maintaining a sub-atmospheric pressure within the cell.

In testimony whereof, I atix my signature.

CLINTON PAUL TOWNSEND. 

